Progeny Varicella-Zoster Virus Capsids Exit the Nucleus but Never Undergo Secondary Envelopment during Autophagic Flux Inhibition by Bafilomycin A1

Girsch, James H.; Walters, Katherine; Jackson, Wallen; Grose, Charles

Reexamination of micrographs of BAF-treated infected cells. After viewing the BAF-treated uninfected cells, we reexamined the changes in organelles in the cytoplasm of BAF-treated infected cells. In particular, we found disassembly of the Golgi apparatus as a prominent feature (Fig. 7A to D) . Intact Golgi apparatuses with stacks of cisternae were rarely present. We were unable to locate any capsids in the cytoplasm that were encircled by Golgi apparatus membranes as evidence of secondary envelopment. We observed numerous MVBs. We also observed an occasional endosome that contained not only vesicles, but also fragments of Golgi apparatus stacks ( Fig. 7B and C). Other cytoplasmic vacuoles contained additional, even larger portions of the Golgi apparatus (Fig. 7D) . These MVBs were not found in untreated VZV-infected cultures ( Fig. 7E and F) . We observed a second major difference in BAF-treated infected cultures. By the third day of a typical VZV infection, numerous virus-filled vacuoles were seen in the cytoplasm, and viral particles (both virions and light particles) were seen along the plasma membrane ( Fig. 7E and F) . In contrast to untreated infected cultures, the cytoplasm in BAF-treated monolayers was not filled with transport vacuoles containing 1 to 4 prototypical enveloped viral particles, and viral particles were not aligned along the plasma membrane (Fig. 7A) . These observations further documented that secondarily enveloped viral particles were not seen in BAF-treated cells.